Inventors:
John E. Cromwell - Baltimore MD
Nicholas Herbert - Baltimore MD
Glenn F. Hyde - Timonium MD
Assignee:
Koppers Company, Inc. - Pittsburgh PA
International Classification:
B23P 1506
Abstract:
A method of making piston rings comprising forming annular stepped grooves in the outer periphery of a plurality of piston ring blanks, stacking the blanks on a rotatable arbor, electro-depositing a layer of chromium in the grooves and on the outer surfacs of the ring blanks, and removing an outer portion of the chromium layer and the outer bearing faces of the ring blanks to form a plurality of piston rings having a continually axially convex surface on the face of the ring formed by the deposited chromium and bearing faces of the ring.